Transcriptomic and metabolomic study of the biosynthetic pathways of bioactive components in Amomum tsaoko fruits

Amomum tsaoko is a significant medicinal and edible plant with documented efficacy in the treatment of various diseases. Additionally, it is a crucial food additive and spice. 1,8-cineole and curcumin are the main bioactive compounds of A. tsaoko, and research on these compounds has mainly focused on their chemical composition and pharmacological activity, with relatively less exploration of synthetic pathways and identification of key genes. This study employed transcriptome sequencing and metabolomic analysis of A. tsaoko at five different developmental stages (May fruit - September fruit) to assess the accumulation patterns of terpenoid and curcuminoid compounds and to explore the key genes and transcription factors (TFs) involved in their synthesis pathways. The results showed that three genes encoding 1-deoxy-D-xylulose-5-phosphate synthase (DXS), hydroxymethylglutaryl-CoA synthase (HMGCS) and phosphomevalonate kinase (mvaK2) and TFs such as AP2-ERF, bHLH, WRKY were screened for involvement in terpenoid biosynthesis. In addition, three genes encoding trans-cinnamate 4-monooxygenase (C4H), curcumin synthase (CURS) and TFs such as MYB, bHLH, bZIP were screened for involvement in curcuminoid biosynthesis. This study provides a theoretical foundation for further research into the biosynthesis of active components in A. tsaoko, establishing a basis for in-depth investigations into the mechanisms underlying its medicinal quality formation. Additionally, it offers guidance for the utilisation of its aromatic components and natural pigments.